It seems to me that 2020 is unlikely. I suspect that Xi Jinping has decided that it's not on in the short term and that is why he has made it possible for himself to seek further terms in office and to wait for a time when America's resolve may have diminished. He eyes his place on the pantheon and to be up there with the greats you have to have reunited China - a country that has continually split and come together again over the centuries. On the other hand, nothing that China does ceases to surprise me.